During the action of a uhf electromagnetic field with a frequency of 48 MHz and of nonthermogenic intensity, the concentration of lactic and pyruvic acids in the rat brain tissue rises while the glycogen content falls. These effects are dependent on the intensity of the field and the duration of its action. In the case of prolonged exposure to a field of intensity 800 W/m, the lactic acid concentration in the brain remains elevated one month after the end of exposure.
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